Portable ramps are used in a variety of applications, such as to allow a person, cargo, vehicle and/or other items to move between an upper and a lower surface or to span a gap between surfaces on the same level.
One application where ramps are used is to provide access to the back of a truck or trailer. The bed of a cargo area of a truck or trailer is usually located above the ground. If the truck or trailer is not backed up to a loading dock having the appropriate height then loading and unloading is made more difficult due to the height difference between the ground and the bed of the truck or trailer. Cargo areas of trucks and trailers are loaded and unloaded daily across the country, in various environments, and in various weather conditions. When ramps are used to provide access to the cargo areas of trucks and trailers that are unloaded outside or areas that are not temperature controlled, those ramps will be subject to the environmental conditions. When those conditions provide temperatures that are near, at, or below the freezing point of water, there is a risk that moisture that might accumulate on the ramp will freeze or partially freeze. Such freezing can create a slippery, and unsafe, condition on the ramp. Slippery conditions can also be created on the ramp by falling snow accumulating on the ramp surface.
Even when ramps are provided with a course upper surface to provide improved grip, moisture can freeze or snow can accumulate on the ramp surface and create a slippery condition, such as when the freezing water or snow accumulates over the grip surface. It is well known that frozen moisture or snow can sometimes be difficult to see. In addition, if workers are carrying freight that obstructs their view of the ground when loading or unloading, even frozen moisture or snow that would be otherwise visible might not be seen may a worker carrying such freight. As a ramp is often used between two surfaces of different heights, the angled nature of the ramp will increase slip and fall risks over such risks on a level surface.
The present inventor recognized that despite all appropriate care, many workers each year are injured by slipping on snow or frozen moisture present on a ramp. The present inventor recognized it would be desirable to provide a portable surface that reduced the slip and fall risks in snowy or freezing conditions. The present inventor recognized it would be desirable to provide a heat source under the portable surface to prevent moisture from freezing and snow from accumulating on the surface.
The present inventor recognized that it would be desirable to provide a method of manufacturing a portable heated ramp. The present inventor recognized that it would be desirable to provide a method of retro-fitting existing portable ramps with a heating capability.